Just here the other day, I learned the biddle trick. I soon realised what an amazing trick this actually is, although it's so easy. And then I began to wonder: Are there lots of other tricks like this? So, I want you to mention your favourite classic effects, that's hard hitting, yet relatively simple. I'm not talking of spanking new, advanced effects like T11 or E material. I mean the old, classic effects that are so simple, yet with tremendous potential, like 2 Card Monte, Biddle trick, ACR and so on 
